From: David Disseldorp <ddiss@suse.de>
Date: Wed, 3 May 2017 22:41:13 +0000 (+0200)
Subject: cifs: fix CIFS_IOC_GET_MNT_INFO oops
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d8a6e505d6bba2250852fbc1c1c86fe68aaf9af3;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

cifs: fix CIFS_IOC_GET_MNT_INFO oops

An open directory may have a NULL private_data pointer prior to readdir.

Fixes: 0de1f4c6f6c0 ("Add way to query server fs info for smb3")
Cc: stable@vger.kernel.org
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Steve French <smfrench@gmail.com>
---

diff --git a/fs/cifs/ioctl.c b/fs/cifs/ioctl.c
index 4d598a71cf84..76fb0917dc8c 100644
--- a/fs/cifs/ioctl.c
+++ b/fs/cifs/ioctl.c
@@ -209,6 +209,8 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 				rc = -EOPNOTSUPP;
 			break;
 		case CIFS_IOC_GET_MNT_INFO:
+			if (pSMBFile == NULL)
+				break;
 			tcon = tlink_tcon(pSMBFile->tlink);
 			rc = smb_mnt_get_fsinfo(xid, tcon, (void __user *)arg);
 			break;